Encyclopedia of artificial intelligence : volume 1
John Wiley & Sons, 1987
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The Handbook of artificial intelligence volume 2
edited by Avron Barr; Edward A. Feigenbaum
Addison-Wesley, 1982
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Encyclopedia of knowledge : volume 2
Grolier Incorporated, 1991
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The Encyclopedia Americana : volume 2
Grolier, 1994
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Encyclopedia of bioethics : volume 2
Warren Thomas Reich, editor in chief
Simon & Schuster Macmillan, 1995
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